This essay argues that the apparent discrepancies between oral tradition and other kinds of historical evidence in the western Serengeti, Tanzania, result from a rupture in time and space. As people were incorporated into a meta-ethnic region to the east dominated by the Maasai in the last half of the nineteenth century, they created new ways of calculating time and organizing space based on new kinds of age-sets. Within this larger context of widespread disasters the small, unconsolidated western Serengeti ethnic groups that we now know as Nata, Ikoma, Ishenyi and Ngoreme formed their identities. New generational and gender contests of power came into play as western Serengeti peoples responded creatively to the pressures of the late nineteenth century by mobilizing their own internal cultural resources.